<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<script>
			//是否是数字
			//负数， -13
			//小数点的问题
			/*var num=window.prompt("请输入数字：");
			var regnum=/^-?\d+(\.\d+)?$/;//
			alert(regnum.test(num));*/
			
			var guhua=/^(\d{3,4}-)?\d{7,8}$/;
			alert(guhua.test("0551-62905330"));
		</script>
	</head>
	<body>
	</body>
</html>
